System for producing piles moulded in the ground

ABSTRACT

System for producing ground-moulded piles. A pressure gauge capsule exposed to the concrete in the concrete supply pipe controls the extraction of the tubing through which the concrete is supplied to the bore in such manner as to stop the extraction when a parameter of the flow of the concrete in the supply pipe passes through a predetermined threshold value.

United States Patent Parez [451 Apr. 25, 1 972 [54] SYSTEM FOR PRODUCING PILES MOULDED IN THE GROUND [72] Inventor: Louis Albert Perez, 4, Place de Mexico,

75 Paris, France [22] Filed: June 1, 1970 [21] Appl.No.: 42,191

I30) Foreign Application Priority Data June 17, 1969 France ..6920064 I52] U.S. Cl ..61/53.64, 73/262 [51] lnt.Cl ..E02d 5/38,G01f 3/20 [58] Field of Search ..6l/53.64, 53.66, 53.5, 53.52; 73/262; 137/557 [56] References Cited UNITED STATES PATENTS 3,200,599 8/1965 Phares et al. ..61/53.64

3,163,529 12/1964 Jewett ..73/406 3,434,294 3/1969 Hall ..6l/53.64

FOREIGN PATENTS OR APPLlCATlONS 1,212,899 1966 Germany ..6l/53.64

Primary Examiner-Jacob Shapiro Attorney-Lester W. Clark, Robert S. Dunham, P. E. Henninger, Thomas F. Moran, Gerald W. Griffin, R. Bradlee Boal, Christopher C. Dunham and Robert Scovey ABSTRACT System for producing ground-moulded piles. A pressure gauge capsule exposed to the concrete in the concrete supply pipe controls the extraction of the tubing through which the concrete is supplied to the bore in such manner as to stop the extraction when a parameter of the flow of the concrete in the supply pipe passes through a predetermined threshold value.

1 3 Claims, 1 Drawing Figure SYSTEM FOR PRODUCING PILES MOULDED IN THE GROUND The present invention relates to the production of piles which are moulded in the ground.

It is known that to produce ground-moulded piles, whether they be bored, hammered, or produced by sinking a hollow screw, the concrete is usually introduced in a tube which must be subsequently extracted from the ground.

ln the ensuing description it will be convenient to term tubing" the assembly comprising a concrete supply conduit surrounded by an outer case constituting a coffrage or mounted in a hollow screw.

In the course of the extraction of the tubing, various things might happen which seriously compromise the strength of the pile. Only the sustained attention and the experience of the specialists carrying out this work can avoid these incidents.

It is therefore necessary to try to avoid this permanent supervision and at the same time eliminate most of the causes of incidents.

The object of the invention is to provide an improved system for producing piles moulded in the ground which comprises a tubing adapted to be driven into the ground and in which is provided a concrete supply pipe and an apparatus for extracting said tubing, said system comprising means responsive to a parameter of the flow of the concrete and adapted to control the operation or stoppage of the tubing-extracting apparatus according as the concrete flow parameter detected by said responsive means reaches a predetermined threshold value or does not reach this value.

This arrangement ensures the extraction of the tubing so long as the concrete is supplied under good conditions and the automatic stoppage of the extraction as soon as the responsive means detects something abnormal, by action on the extracting apparatus.

Further features and advantages of the invention will be apparent from the ensuing description with reference to the accompanying drawing.

In the drawing, the FIGURE is a diagrammatic view of an improved system according to the invention for producing piles moulded in the ground.

The illustrated embodiment is considered as being applied to a system for producing piles moulded in the ground with a temporary cover.

This system comprises tubing 1 partly sunk into a boring F and supported at the end of a cable by an extracting apparatus comprising a jib 2 and a winch 3 which is driven by a motor 4 through a clutch 5.

The tubing 1 is provided at its end engaged in the bore with a closing member 6 provided with a centre aperture in which is secured a supply pipe 7 for concrete under pressure supplied by a concrete pump (not shown).

Mounted near the end of the pipe 7 engaged in the closing member 6, is responsive means such as a pressure-gauge capsule 8 which is connected by conductors 9 to a source of current such as a battery of accumulators l placed on the ground level.

The pressure-gauge capsule can be advantageously constructed in the form of an electric switch whose moving contact is integral with an elastically yieldable membrane exposed to the concrete flowing in the pipe 7. Connected to the terminals of the battery 10 in series with the capsule 8 is the coil of an electromagnetic valve 11 which forms part of a circuit of a device controlling the extracting apparatus 5. In the illustrated embodiment, this control device comprises, in addition to the valve 11, a hydraulic pump 12 adapted to control the clutch by applying to the latter a fluid pressure by way of a conduit 13.

The working fluid of the pump 12 is supplied by a tank 14 with which communicate the discharge conduit 15 of the valve 11 and the discharge conduit 17 of a manually controlled distributor valve 16.

The system just described operates in the following manner:

When, in the course of the production of a ground-moulded pile, the concrete is supplied correctly by way of the pipe 7 sunk with the tubing 1, the pressure gauge capsule detects no pressure variation and the coil of the valve is supplied with current in a normal manner.

The connections of the coil are arranged in such manner that under normal conditions the valve 11 is open and the pump 12 therefore applies to the clutch 5 the fluid pressure necessary to ensure that the motor 4 drives the winch 3. The extraction of the tubing 1 is therefore carried out normally.

However, if for any reason, such as an excessively rapid extraction of the tubing relative to the supply of concrete, the capsule 8 detects a drop in pressure in the pipe 7 below a predetermined value it cuts off the supply to the coil of the valve 11 and the latter causes the conduit 13 to be closed and stops the supply of fluid to the clutch 5 by the pump 12. As the clutch 5 is no longer supplied with fluid, the winch 3 is no longer driven by the motor and the extraction of the tubing 1 is stopped.

The fluid supplied by the pump is then pumped back to the tank 14 by way of the discharge conduit 15.

The stoppage of the extraction of the tube results in a progressive rise in the pressure of the concrete in the pipe 7. When this pressure once more reaches a correct predetermined value, for example 5 bars, the capsule 8 once more causes the closure of the supply circuit of the coil of the valve and the latter opens and the pump 12 once again supplies the clutch 5 with fluid. The tubing 2 is once again extracted and the extraction continues until some further detection of a subsequent abnormality by the capsule 8.

If for any reason it is desired to stop the extraction of the tubing 1, the manually controlled distributor 16 is actuated. The fluid delivered by the pump 12 is sent back to the tank 14 by way of the conduit 17 and, as the clutch 5 is no longer supplied with fluid, the winch 3 is no longer driven by the motor 4.

In the embodiment just described the capsule 8 is operatively connected to the tubing-extracting apparatus electrically, but it must be understood that this connection can be achieved hydraulically, pneumatically, mechanically or in any other suitable manner.

Further, the tubing can be extracted by means other than the device having a clutch described hereinbefore.

The pressure-gauge capsule 8 can for example be directly connected in the supply circuit of the motor 4 which actuates the winch 3. Alternatively, the conduit 13 controlled by the electromagnetic valve 11 can be connected to jacks or any other tubing-extracting apparatus.

Having now described my invention what I claim and desire to secure by Letters Patent is:

1. In a system for producing ground-moulded piles, comprising tubing which is adapted to be sunk into the ground, a concrete supply pipe within said tubing, an apparatus for extracting said tubing from the ground as the moulding of the pile proceeds, means responsive to a parameter of the flow of the concrete in said pipe and associated with said tubing-extracting apparatus in such manner as to cause operation or stoppage of said apparatus according to whether the concrete flow parameter detected by said responsive means reaches or not a predetermined threshold value, the improvement wherein said responsive means is a pressure responsive electric switch having a flexible membrane exposed to the concrete flowing in said supply pipe, said pressure responsive switch being connected in acircuit comprising an electromagnetic valve which controls the operation of said tubing-extracting apparatus, the closure or opening of said valve being controlled by said pressure responsive switch.

2. A system as claimed in claim 1, wherein said extracting apparatus comprises a clutch which is controlled by said electromagnetic valve.

3. A system as claimed in claim 2, comprising a hydraulic pump for actuating said clutch, said pump having a circuit in which said electromagnetic valve is inserted. 

1. In a system for producing ground-moulded piles, comprising tubing which is adapted to be sunk into the ground, a concrete supply pipe within said tubing, an apparatus for extracting said tubing from the ground as the moulding of the pile proceeds, means responsive to a parameter of the flow of the concrete in said pipe and associated with said tubing-extracting apparatus in such manner as to cause operation oR stoppage of said apparatus according to whether the concrete flow parameter detected by said responsive means reaches or not a predetermined threshold value, the improvement wherein said responsive means is a pressure responsive electric switch having a flexible membrane exposed to the concrete flowing in said supply pipe, said pressure responsive switch being connected in a circuit comprising an electromagnetic valve which controls the operation of said tubing-extracting apparatus, the closure or opening of said valve being controlled by said pressure responsive switch.
 2. A system as claimed in claim 1, wherein said extracting apparatus comprises a clutch which is controlled by said electromagnetic valve.
 3. A system as claimed in claim 2, comprising a hydraulic pump for actuating said clutch, said pump having a circuit in which said electromagnetic valve is inserted. 